The default database of user manager is the H2 database that comes with WSO2 products. You can configure it to point to databases by other vendors such as IBM DB2, Oracle, MySQL using the scripts provided by WSO2 for installing and configuring relational databases. The scripts in <PRODUCT_HOME>/dbscript folder are available in all WSO2 products. They store data related to WSO2 Carbon, on top of which all WSO2 products are built. There is a separate set of database scripts in <PRODUCT_HOME>/dbscript/apimgt folder. These scripts are to create databases that store API Manager-specific data.
Each database you create supports stored procedures, which allow business logic to be embedded inside the database as an API, providing a powerful mechanism for interacting with a relational database. Because stored procedures are stored in a precompiled format within the database itself, execution speed is much faster. Client programs can be restricted to accessing a database via stored procedures only, thereby enforcing fine-grained security, preservation of data integrity, and improved productivity.
After you set up the physical database, you add data sources in the Management Console to enable the server to connect to that database.